Male luer lock connector

ABSTRACT

Connector for medical use comprising: a body joined to a line or adapted to be connected at one of its ends to a tubing in which a fluid flows, and a male luer lock connection comprising a base mounted rotatingly on the body and cooperating by friction with it, without any possible translational movement. The base is joined to a hollow tubular body, having a threaded inner surface and a male central luer cone. The outer surface of the body and the inner surface of the base of the connection, cooperating by friction, have a spherical then cylindrical shape.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage filing under section 371 of International Application No. PCT/FR2007/051308, filed on May 22, 2007, and published in French on Nov. 29, 2007 as WO 2007/135337 A1 and claims priority of French application No. 0604659 filed on May 24, 2006, the entire disclosure of these applications being hereby incorporated herein by reference.

The invention relates to a connector for medical use. It relates more particularly to a male luer lock connector intended to cooperate with a female luer connector in order to connect a liquid line.

Two types of luer lock connector are available on the market today.

The first range consists of connectors in which a male luer lock connection is mounted rotatingly on a tubular body joined to the fluid inlet tubing. In this type of connector, the connection cannot move translationally, and can only rotate. In practice, the connection is provided with a thread for screwing to the female luer end piece. To guarantee the tightness, an O-ring is positioned between the inner surface of the connection and the outer surface of the body. This form of connector is described for example in document DE 373 76 65.

The other range of connectors is for example the one illustrated in document EP-A-1 236 481. Unlike the luer lock connectors described above, the connection here does not only rotate about the tubular body but also moves translationally along the body. A stop is arranged on the body in order to limit the travel of the ring and consequently its separation from the body. The connection to the female luer is also provided by screwing. This type of connector has a major drawback: when tightened, that is when the male luer and the female luer are joined together, the mobile ring tends to loosen because of the stress between the internal threads of the ring and the stop limiting its translational movement. In other words, the ring tends to unscrew and then no longer performs its locking function. This incurs a risk of leaks, or even of disconnection.

It is the object of the present invention to improve the first range of connectors. The devices described in document DE 373 76 65 have a number of drawbacks. Firstly, the risk of disconnection of the male luer from the body subsists. This is because in this document, the male luer connection is joined to the body by clipping the male luer connector using a band arranged on the whole periphery of the body. According to the pressure applied in the connector, the system may be disconnected because of the rounded shape of the said band. Moreover, the cost of this type of product is high due to the presence of three parts, respectively a body, a connection and a seal.

In other words, the problem that the invention proposes to solve is to develop a luer lock connector that has no seal, in order to decrease the cost of the product, but which nevertheless remains perfectly leaktight without any risk of disconnection of the ring from the body.

To solve this problem, the Applicant has developed a specific body shape, cooperating by friction with a matching shape arranged at the end of the connection, in the absence of any seal.

BRIEF SUMMARY OF THE INVENTION

More precisely, the invention relates to a connector for medical use comprising:

-   -   a body joined to a line or intended to be connected at one of         its ends to a tubing in which a fluid flows,     -   a male luer lock connection comprising a base mounted rotatingly         on the body and cooperating by friction with it, without any         possible translational movement, the base being joined to a         hollow tubular body, whereof the inner surface is provided with         a thread and whereof the centre is provided with a male luer         cone.

This connector is characterized in that it has no seal and in that the outer surface of the body and the inner surface of the base of the connection, cooperating by friction, have a spherical then cylindrical shape.

According to the invention, the connector body is joined to a line or is suitable for connection to a line. In the first case, reference is made to ramps, valves or Y-piece connectors whereof the end directly has the shape of the body of the connector of the invention. The second case hypothesises that the body of the connector of the invention is connected by adhesive to a flexible tubing in which a fluid flows.

The essential feature of the connector is to have a spherical then cylindrical shape in the body and the base of the connection.

Whether the connector is used for perfusion, which accounts for most of the cases, or for sampling, the spherical then cylindrical zones may be arranged in any direction towards the terminal end of the body. This spherical part may be followed by the cylindrical part or vice versa. Regardless of the shape of the body, the base of the male luer lock connection has a matching shape cooperating by friction with the matching shape of the body.

The connectors in which the body has a spherical then cylindrical shape in the direction of its free terminal end are more particularly described below.

When the connector is intended for connection to a flexible tubing, the spherical zone of the body is preceded by a linkage zone whereof the outer surface has any shape, generally conical or cylindrical. In this case, the flexible tubing is connecting in the channel formed at the centre of the linkage zone. In practice, the linkage zone is cylindrical and has a diameter d₅, lower than the diameter d₁ of the spherical portion of the body.

When the connector is joined to a ramp, a valve or a Y-piece connector, the spherical then cylindrical parts are moulded directly at the time of their fabrication.

The various embodiments of the body and the matching connection will now be described in greater detail.

In a first embodiment,

the outer surface of the body has at least two successive lengths, respectively:

-   -   a first length in the form of a portion of sphere having         diameter d₁,     -   a second cylindrical length having diameter d₂ lower than d₁,

the inner surface of the base having:

-   -   a first zone in the form of a portion of sphere having a         diameter d₇ substantially equal to d₁,         a second tubular zone, having a diameter d₃ slightly lower than         d₂.

In this case, the seal and hence the clamping of the connection to the connector body is provided by close contact between the cylindrical length of the body and the matching cylindrical length of the base of the connection, whereof the diameter d₃ is slightly lower than d₂ in order to be force fitted into one another. The spherical zone performs the function of joining and clipping the body to the base.

In an advantageous embodiment:

the outer surface of the body has at least three successive lengths, respectively:

-   -   a first cylindrical length having diameter d₄,     -   a second length in the form of a portion of sphere, the diameter         d₄ being substantially equal to the diameter d₁ of the largest         cross section of the portion of sphere,     -   a third cylindrical length having diameter d₂ lower than d₁,

the inner surface of the base has:

-   -   a first zone in the form of a portion of sphere having diameter         d₇ substantially equal to d₁,     -   a second tubular zone having diameter d₃ slightly lower than d₂.

In this case, the connector has two leaktight zones. The first leaktight zone is provided by the close contact between the third cylindrical length and the matching cylindrical length of the base of the connection, whereof the diameter d₃ is slightly lower than d₂. The second leaktight zone is provided by the close contact between the edge of the first cylindrical length having diameter d₄ of the body and the spherical shape of the base having diameter d₁. The spherical zone preserves its original function of joining and clipping.

Regardless of the embodiment of the connector, the spherical zone of the base may be preceded by an advantageously tubular zone having inside diameter d₆ lower than d₁, this zone being intended to clamp either the line of the ramp or the linkage zone having diameter d₅ of the connector when the latter is arranged at the end of a flexible tubing. In practice, d₅ is lower than or equal to d₆.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The invention and the advantages thereof will appear more clearly from the following exemplary embodiments, in conjunction with the appended figures.

FIG. 1 shows a cross section of the connector of the invention.

FIG. 2 shows a cross section of the body.

FIG. 3 shows a cross section of the connection.

DETAILED DESCRIPTION

FIG. 1 shows a male luer lock connector like the one of the invention. This connector consists of two distinct parts, respectively a body (1) and a male luer connection (2).

The body (1) is suitable for connection by its end (3) to a fluid tubing not shown. In practice, the fluid tubing is connected to the body by fitting and then bonding in the channel (4). At its opposite end (5), the body cooperates by friction with the base (6) of the connection (2). In practice, the contact applied between the inner surface of the base (6) and the outer surface of the terminal end (5) of the body (1) causes the rotation of the connection about the body without any possibility of translational movement. In its terminal portion, the male luer connection is a conventional coupling consisting of a hollow body (7) comprising a wall (8), whereof the inner surface (9) is provided with a thread for screwing and hence locking the female luer after connection. The hollow body further comprises a central conical male luer channel (10).

FIG. 2 shows a cross section of the body (1). According to the invention, this body has four distinct successive zones, respectively,

-   -   upstream, a zone called a linkage zone having an outer tubular         surface (11) with diameter d₅,     -   followed by a first cylindrical length (12) having outside         diameter d₄ greater than d₅,     -   then a second length (13) in the form of a portion of sphere         having diameter d₁ of which the largest cross section is         substantially equal to d₄,         and a third length (14) having a tubular shape and a diameter d₂         lower than d₁.

As already stated, the body is provided at its centre with a channel (4) in which the fluid flows. This channel has a first cross section then a lower cross section (15) having a lower diameter, substantially equal to the cross section of the male luer channel (10).

The luer lock connection will now be described in detail.

As shown in FIG. 3, the base (6) has a first tubular zone (16), whereof the diameter of the inner surface d₆ is substantially equal to the diameter d₅ of the linkage zone of the body. Moreover, the base has a first length (17) having a spherical shape whereof the diameter d₇ is substantially equal to that of the largest cross section of the portion of sphere having diameter d₁ of the body. Finally, the base of the connection has a second tubular zone (18) having a tubular shape, whereof the diameter d₃ is substantially equal to that of the diameter d₂ of the body (1).

In this way, the clipping of the connection (2) to the body (1) creates two leaktight zones. The superimposition of the terminal cylindrical zone (14) of the body (1) with the matching zone (18) of the base ensures the primary seal of the system owing to the diameter of d₃<d₂ and hence of the force fitting of the two elements together. The interference zone existing between the edge (19) of the cylindrical zone (12) of the body and the spherical zone (17) of the base guarantees a secondary seal.

The invention and the advantages thereof will appear clearly from the above description. A friction zone may be observed in particular, having a specific shape and serving to guarantee the seal of the connector without any risk of disconnection and in the absence of a seal. 

1. A connector for medical use comprising: a body joined to a line or adapted to be connected at one end to a tubing in which a fluid flows, a male luer lock connection comprising a base mounted rotatingly on the body and cooperating by friction with the body, without any possible translational movement, the base being joined to a hollow tubular body, having a threaded inner surface and a central male luer cone, wherein the connector has no additional element that acts as a seal between the body and the base, and an outer surface of the body and an inner surface of the base cooperate by friction, the outer surface of the body having at least two successive lengths, respectively: a first length in the form of a portion of sphere having diameter d₁, and a second cylindrical length having diameter d₂ smaller than d₁; and the inner surface of the base having: a first zone in the form of a portion of sphere having a diameter d₇ substantially equal to d₁, and a second tubular zone, having a diameter d₃ slightly smaller than d₂; and wherein the outer surface of the body further includes an additional cylindrical length having diameter d₄, the additional cylindrical length preceding the first length, the diameter d₄ being substantially equal to the diameter d₁ of the largest cross section of the portion of sphere.
 2. The connector according to claim 1, wherein the first zone is preceded by a tubular zone having diameter d₆ smaller than d₁.
 3. The connector according to claim 1, wherein the first length is preceded by a linkage zone having a diameter d₅ and an outer surface of any shape.
 4. A valve equipped with the connector of claim
 1. 5. A ramp equipped with the connector of claim
 1. 6. A Y-piece connector equipped with the connector of claim
 1. 7. A perfusion tube equipped with the connector of claim
 1. 8. An extension equipped with the connector of claim
 1. 